fix(#435): fix scope value for strava (#484)

Author: chrl

providers/strava/strava.go

@@ -10,6 +10,7 @@ import (
 	"io/ioutil"
 	"net/http"
 	"net/url"
+	"strings"
 
 	"github.com/markbates/goth"
 	"golang.org/x/oauth2"
@@ -157,9 +158,7 @@ func newConfig(provider *Provider, scopes []string) *oauth2.Config {
 	}
 
 	if len(scopes) > 0 {
-		for _, scope := range scopes {
-			c.Scopes = append(c.Scopes, scope)
-		}
+		c.Scopes = []string{strings.Join(scopes, ",")}
 	} else {
 		c.Scopes = []string{"read"}
 	}